Molds belong to the kingdom known as fungi. This kingdom is part of the five-kingdom classification system introduced by R.H. Whittaker in 1959 that gave fungi equal status with plants and animals. Molds, as well as other fungi, are eukaryotic organisms that are considered distinct from plants and animals.
In addition to belonging to the kingdom of fungi, molds can be placed in several phyla of fungi, which include the Zygomycota, Ascomycota, Oomycota, Basidiomycota and Chytridiomycota. Zygomycota contains a mold found on bread known as Rhizopus stolonifera. Black molds are found in the phylum Ascomycota. Oomyota contains saprophytic water molds and tobacco blue mold.